Many communications devices, such as radios, typically include a rotary switch which is movable to a number of positions. In a rotary switch for a handheld satellite transceiver and other portable communications devices, these positions typically include “off,” “channels 1-5” (or more), “scan,” “front panel,” and, “Z-all” or “reset.” Generally, the reset position resets the transceiver by clearing all encryption cipher keys inputted by a user. The front panel position is typically used for allowing the channels and modes of operation to be selected using the key pad on the front panel of the transceiver.
Although the operation of many rotary switch designs is straightforward, many permit the transceiver to be inadvertently turned off by a user turning the rotary switch too far. In such an event, the user must then turn the transceiver back on to resume communication. In some devices, such as satellite transceivers, a reboot period of significant length is required, delaying resumption of communications. Typical switch designs may also permit inadvertent movement of the rotary switch to the reset position. Although some designs of satellite transceivers prevent resetting in the reset position by requiring actuation of a second button, the user may still inadvertently reset the satellite transceiver.
Some satellite transceiver designs have been proposed using “push-to-turn” rotary switches, in which pressure must be applied to the stem of the rotary switch prior switching positions. However, the stem may still be inadvertently pushed and the satellite transceiver may be reset or turned off. Other switch assembly designs have been proposed using “pull-to-turn” rotary switches in which the user must pull on the stem while changing positions. However, such switches typically require additional complexity within the rotary switch, as the pull-to-turn or push-to-turn functionality is typically included within the body of the rotary switch. This also results in switch bodies that are typically larger than those typically used in satellite transceivers, increasing the overall size of the satellite transceiver. In systems where the pull-to-turn or push-to-turn functionality is included in the knob, a groove system is typically used. However, such groove systems can be susceptible to dirt, sand, or grit, resulting in seizing or poor operation of the rotary switch. Therefore, there is a need for an improved device for controlling the operation of rotary switches in communications devices.